Acoustic frequency interrogation and data system

ABSTRACT

A system, in certain embodiments, includes a subsea acoustic frequency interrogation and data system. The subsea acoustic frequency interrogation and data system includes a master acoustic transceiver configured to broadcast an acoustic activation signal and an acoustic frequency interrogated data transmitter configured to generate power from the acoustic activation signal and activate a sensor configured to measure an operating parameter of subsea equipment.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.13/403,222, entitled “Acoustic Frequency Interrogation and Data System,”filed on Feb. 23, 2012, which is hereby incorporated by reference in itsentirety.

BACKGROUND

This section is intended to introduce the reader to various aspects ofart that may be related to various aspects of the present invention,which are described and/or claimed below. This discussion is believed tobe helpful in providing the reader with background information tofacilitate a better understanding of the various aspects of the presentinvention. Accordingly, it should be understood that these statementsare to be read in this light, and not as admissions of prior art.

A variety of subsea equipment, such as mineral extraction equipment, mayinclude subsea instrumentation systems. For example, subsea blowoutpreventer (BOP) stacks, drilling riser systems, subsea production trees,and other equipment may include subsea instrumentation systems. Thesubsea instrumentation systems generally include wired sensors formonitoring various operating parameters, such as temperature andpressure, of the subsea equipment. Subsea instrumentation cablesconnected to the wired sensors provide power to the sensors and transmitmeasurements taken by the sensors. In addition, the number of subseacables used may increase to satisfy redundancy of measurementrequirements to improve overall reliability of subsea instrumentation.Unfortunately, subsea cables and connectors used with subsea equipmentcan have high costs.

BRIEF DESCRIPTION OF THE DRAWINGS

Various features, aspects, and advantages of the present invention willbecome better understood when the following detailed description is readwith reference to the accompanying figures in which like charactersrepresent like parts throughout the figures, wherein:

FIG. 1 is a sub-sea BOP stack assembly, which may include an acousticfrequency interrogation and data system;

FIG. 2 is a sub-sea BOP stack assembly, which may include an acousticfrequency interrogation and data system;

FIG. 3 is an embodiment of master acoustic transceiver configured tobroadcast a high-power acoustic activation signal to one or moreacoustic frequency interrogated data transmitters;

FIG. 4 is an embodiment of an acoustic frequency interrogated datatransmitter configured to generate locally stored power from ahigh-powered acoustic signal;

FIG. 5 is a schematic illustrating an embodiment of the electronicscircuitry of the master acoustic transceiver; and

FIG. 6 is a schematic illustrating an embodiment of the electronicscircuitry of the acoustic frequency interrogated data transmitter.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

One or more specific embodiments of the present invention will bedescribed below. These described embodiments are only exemplary of thepresent invention. Additionally, in an effort to provide a concisedescription of these exemplary embodiments, all features of an actualimplementation may not be described in the specification. It should beappreciated that in the development of any such actual implementation,as in any engineering or design project, numerousimplementation-specific decisions must be made to achieve thedevelopers' specific goals, such as compliance with system-related andbusiness-related constraints, which may vary from one implementation toanother. Moreover, it should be appreciated that such a developmenteffort might be complex and time consuming, but would nevertheless be aroutine undertaking of design, fabrication, and manufacture for those ofordinary skill having the benefit of this disclosure.

When introducing elements of various embodiments of the presentinvention, the articles “a,” “an,” “the,” and “said” are intended tomean that there are one or more of the elements. The terms “comprising,”“including,” and “having” are intended to be inclusive and mean thatthere may be additional elements other than the listed elements.Moreover, the use of “top,” “bottom,” “above,” “below,” and variationsof these terms is made for convenience, but does not require anyparticular orientation of the components.

Subsea equipment may include subsea instrumentation systems havingsensors configured to measure various operating parameters of the subseaequipment. For example, the sensors may be configured to measuretemperature or pressure of production fluid, fracing fluid, vessels,tanks, and so forth. As discussed in detail below, subsea equipment mayinclude an acoustic frequency interrogation and data system configuredto measure various operating parameters of the subsea equipment.Specifically, the acoustic frequency interrogation and data systemutilizes acoustic signals to power and communicate with sensors disposedwithin the subsea equipment. A master acoustic transceiver (MAT) may beconfigured to broadcast a high-power acoustic activation signal to oneor more acoustic frequency interrogated data transmitters (AFIDs)positioned on the subsea equipment. Each AFID includes one or moresensors configured to measure an operating parameter of the subseaequipment. Additionally, the AFID uses the high-powered acoustic signalto generate locally stored power and activate the sensor. After thesensor takes a measurement, the AFID acoustically transmits the sensormeasurement to the MAT with an acoustic return signal. In this manner,various operating parameters of the subsea equipment may be monitored bysensors with a reduced need for wired connections. In other words, thenumber of instrumentation cables used for monitoring subsea equipmentprocesses may be reduced.

The acoustic frequency interrogation and data system may be used invarious types of subsea equipment. For example, the acoustic frequencyinterrogation and data system may be used with subsea blowout preventer(BOP) stacks, drilling riser systems, subsea production trees, and otherequipment may include subsea instrumentation housings. Additionally, theacoustic frequency interrogation and data system may be used for otherunderwater equipment or surface equipment, including mineral extractionor other equipment. The following discussion describes an exemplaryembodiment of the acoustic frequency interrogation and data system in asubsea BOP stack context. However, it should be noted that thediscussion is not intended to limit the application of the acousticfrequency interrogation and data system to subsea BOP stacks.

Turning now to the drawings, FIG. 1 depicts a subsea BOP stack assembly10, which includes an acoustic frequency interrogation and data system12 having master acoustic transceivers (MATs) 14 and acoustic frequencyinterrogated data transmitters (AFIDs) 15. As illustrated, the BOP stackassembly 10 is assembled onto a wellhead assembly 16 on the sea floor18. The BOP stack assembly 10 is further connected in line between thewellhead assembly 16 and a floating rig 20 through a subsea riser 22.The BOP stack assembly 10 may provide emergency fluid pressurecontainment in the event that a sudden pressure surge escapes the wellbore 24. Therefore, the BOP stack assembly 10 may be configured toprevent damage to the floating rig 20 and the subsea riser 22 from fluidpressure exceeding design capacities. The BOP stack assembly 10 alsoincludes a BOP lower riser package 26, which connects the subsea riser22 to a BOP package 28.

In certain embodiments, the BOP package 28 may include a frame 30supporting one or more AFIDs 15 configured to measure various operatingparameters of the BOP package 28. Additionally, in other embodiments,AFIDs 15 may be positioned in other areas of the BOP package 28. In theillustrated embodiment, the MATs 14 are attached to supporting arms 32extending laterally from the frame 30 of the BOP package 28. The MATs 14may be further coupled to a subsea instrumentation system 34 by a cableor other connection. In certain embodiments, the subsea instrumentationsystem 34 may be configured to store or further transmit the sensormeasurements collected by the AFIDs 15. As mentioned above, the MATs 14are configured to broadcast a high-power acoustic activation signal 36to the AFIDs 15. The high-power acoustic activation signal 36 activateseach of the AFIDs 15. In other words, the high-power acoustic activationsignal 36 is received by the AFIDs 15, and is used by the AFIDs 15 togenerate locally stored power. As discussed in detail below, the powergenerated by the AFIDs 15 from the high-power acoustic activation signal36 powers sensors which measure various operating parameters of the BOPpackage 28.

FIG. 2 illustrates the subsea BOP stack assembly 10, including the MATs14 and the AFIDs 15 of the acoustic frequency interrogation and datasystem 12. As mentioned above, the AFIDs 15 use power generated from thehigh-power acoustic activation signal 36 broadcasted by the MATs topower and activate sensors within the AFIDs 15. Specifically, thesensors measure various operating parameters, such as temperatures,pressures, flow rates, vibration, chemical composition, etc, of the BOPpackage 28. In this manner, the sensors of the AFIDs 15 may help monitorthe processes of the BOP package 28 without requiring a hard (i.e.,wired) connection between the sensors to the subsea instrumentationsystems 34. Once the sensor measurement is taken, each AFID 15acoustically transmits the sensor measurement to the MATs 14. Inparticular, each AFID 15 sends an acoustic return signal 38 to the MATs14. The MATs 14 may then transmit the sensor measurements to the subseainstrumentation systems 34. As discussed below, the AFIDs 15 send thereturn signals 38 using a protocol, such as an Ethernet protocol, thatenables the AFIDs 15 to communicate with the MATs 14 one at a time.

After the AFIDs 15 transmit the return signals 38 to the MATs 14, theAFIDs 15 wait until another high-power acoustic activation signal 36 issent by the MATs 14. For example, the AFIDs 15 may shut down after thepower generated from the initial high-power acoustic activation signal36 runs out. When the MATs 14 send another high-power acousticactivation signal 36, the AFIDs 15 will again generate power from thesignal 36 and the sensors within the AFIDs will take additional sensormeasurements that will be transmitted to the MATs with the acousticreturn signals 38.

FIG. 3 illustrates an embodiment of the MAT 14 which may be used withthe acoustic frequency interrogation and data system 12. As mentionedabove, the MAT 14 is configured to broadcast the high-power acousticactivation signal 36 to one or more AFIDs 15. In the illustratedembodiment, the MAT 14 is coupled to the subsea instrumentation system34 by a cable 50. As discussed above, the MAT 14 may be coupled to thesubsea instrumentation system 34 by other communication techniques, suchas a wireless connection.

As shown, the MAT 14 includes electronics circuitry 52. The electronicscircuitry 52 is configured to control a transceiver 54 of the MAT 14.For example, the electronics circuitry 52 is configured to generate andcontrol the frequency of the high-power acoustic activation signal 36broadcasted by the transceiver 54 of the MAT 14. In certain embodiments,the high-power acoustic activation signal 36 may be broadcasted by thetransceiver 54 at 30 to 80, 35 to 75, 40 to 60, or 45 to 55 Hertz.Furthermore, in embodiments of the acoustic frequency interrogation anddata system 12 having multiple AFIDs 15, the MAT 14 may communicate witheach AFID 15 using the same frequency or different frequencies.Additionally, the high-power acoustic activation signal 36 may bebroadcasted at different power levels. For example, the high-poweracoustic activation signal 36 may be broadcasted at 2 to 50, 4 to 40, 6to 30, or 8 to 20 watts.

The transceiver 54 broadcasts the high-power acoustic activation signal36 to communicate with the AFIDs 15. For example, in certainembodiments, the high-power acoustic activation signal 36 may include ahigh-power tone and an acoustic message, which may include information,such as a time stamp. As described in detail below, the AFIDs 15 use thehigh-power acoustic activation signal 36 broadcasted by the transceiver54 to power sensors configured to measure operating parameters of theBOP package 28.

The MAT 14 includes a mounting portion 56 and a housing 58, containingthe electronics circuitry 52 and the transceiver 54, which are removablycoupled and may be manufactured from corrosion resistant alloys. Inother words, the mounting portion 56 and the housing 58 of the MAT 14may be selectively disconnected from one another. In this manner, thehousing 58 may be removed from the mounting portion 56 for maintenance,repair, or replacement. For example, the mounting portion 56 may becoupled to or fixed to the supporting arms 32 extending from the BOPpackage 28, and the housing 58 may be coupled to the mounting portion 56with a dry-mate connector 60. The dry-mate connector includes a pin andsocket connection 61 having pins 62 configured to transmit electricalsignals between the subsea instrumentation system 34 and the electronicscircuitry 52. Additionally, the dry-mate connector 60 is configured towithstand a subsea environment. That is, the dry-mate connector 60 maybe configured to withstand elevated pressures and may becorrosion-resistant. Furthermore, the dry-mate connector 60 may bedesigned to be water resistant or waterproof to block sea water fromcontacting the pins 62 when the MAT 14 is in operation. For example, thedry-mate connector 60 includes a seal 64 between the mounting portion 56and the housing 58. The seal 64 is configured to block sea water fromentering the MAT 14 and contacting the pins 62. In certain embodiments,the dry-mate connector 60 may couple the mounting portion 56 and thehousing 58 with a threaded connection or a compression fit connection.Additionally, the dry-mate connector 60 may have a mechanical lockingmechanism.

FIG. 4 illustrates an embodiment of the AFID 15 configured to generatelocally stored power from the high-power acoustic activation signal 36and take sensor measurements from the subsea BOP package 28.Additionally, the AFID is configured to acoustically transmit datacontaining the sensor measurements to the MAT 14. In the illustratedembodiment, the AFID 15 includes a process acoustic module 80 and aprocess sensor module 82, which may be manufactured from corrosionresistant alloys. The process acoustic module 80 is a housing thatencloses a transceiver 84 and electronics circuitry 86, and the processsensor module 82 is a housing that encloses a sensor 88. In certainembodiments, the process sensor module 82 may enclose one or moresensors 88. For example, the process sensor module 82 may enclose 1, 2,3, 4, 5, 6, 7, 8, 9, 10, or more sensors 88. The transceiver 84 isconfigured to receive the high-power acoustic activation signal 36broadcasted by the transceiver 54 of the MAT 14. As shown, thetransceiver 84 is coupled to the electronics circuitry 86. Theelectronics circuitry 86 uses the high-power acoustic activation signal36 to generate power. As discussed below, the power generated by theelectronics circuitry 86 powers the sensor 88 of the AFID 15.

As shown, the process acoustic module 80 and the process sensor module82 are coupled to one another with a dry-mate connector 90. As similarlydescribed above, the dry-mate connector 90 includes a pin in socketconnection having pins 92 configured to transmit electrical signalsbetween the electronics circuitry 86 and the sensor 88. Additionally,the dry-mate connector 90 is configured to withstand subseaenvironments. For example, the dry-mate connector 90 may be capable ofwithstanding elevated pressures and may be corrosion-resistant. Thedry-mate connector 90 may be designed to be water resistant orwaterproof to prevent sea water from contacting the pins 92 when theAFID 15 is in operation. For example, the dry-mate connector 90 includesan annular seal 93 disposed between the process acoustic module 80 andthe process sensor module 82. In certain embodiments, the dry-mateconnector 90 may couple the process acoustic module 80 to the processsensor module 82 with a threaded connection or a compression fitconnection. Furthermore, the dry-mate connector 90 may include amechanical lock configured to block inadvertent disconnection of thedry-mate connector 90.

As mentioned above, the AFID 15 is coupled to the BOP package 28 and isconfigured to measure various operating parameters of the BOP package 28with the sensor 88. Specifically, the process sensor module 82 ispartially disposed within an opening 94 in an exterior surface 96 of theBOP package 28. Additionally, the process sensor module 82 has anopening 98 configured to expose the sensor 88 to an interior 100 of theBOP package 28. In this manner, the sensor 88 may be exposed tooperating conditions, such as temperatures or pressures, within the BOPpackage 28.

The process sensor module 82 may be mounted to the BOP package 28 in avariety of manners. For example, in the illustrated embodiment, theprocess sensor module 82 includes mounting flanges 102 extendinglaterally from the process sensor module 82. The mounting flanges 102include apertures 104 configured to receive fasteners 106, which securethe mounting flanges 102 to the exterior surface 96 of the BOP package28. The fasteners 106 may be bolts or other types of fastener.Additionally, an annular seal 108 is disposed between the mountingflanges 102 and the exterior surface 96 of the BOP package 28. Theannular seal 108 may help block sea water from entering the BOP package28 through the opening 94. Moreover, the annular seal 108 may helpreduce or prevent contents, such as operating fluids, within the BOPpackage 28 from exiting the BOP package 28 through the opening 94. Inother embodiments, the opening 94 in the exterior surface 96 may be athreaded port and the process sensor module 82 may have a threadedexterior. In this manner, the AFID 15 may be coupled to the BOP package28 with a threaded connection.

As mentioned above, the AFID 15 is configured to convert the high-poweracoustic activation signal 36 into power that may be used to power thesensor 88. When the transceiver 84 of the AFID 15 detects the high-poweracoustic activation signal 36, the transceiver 84 sends the signal 36 tothe electronics circuitry 86, which subsequently converts the signal 36into power. The power generated by the electronics circuitry 86 is usedto power the sensor 88. Specifically, once the electronics circuitry 86generates power from the high-power acoustic activation signal 36 andsupplies the power to the sensor 88, the sensor 88 is activated and thesensor 88 begins to take measurements. For example, the sensor 88 maytake a temperature or pressure measurement of the interior 100 of theBOP package 28, in the manner described above. That is, the sensor 88 isexposed to the interior 100 of the BOP package 28 through the opening 94in the exterior surface 96 of the BOP package 28 and through the opening98 in the process sensor module 82.

After the sensor 88 takes a sensor measurement, the sensor measurementis transmitted to the MAT 14. Specifically, the sensor measurement issent from the sensor 88 to the transceiver 84 by the electronicscircuitry 86. Thereafter, the transceiver 84 acoustically sends thesensor measurement to the MAT 14 with the acoustic return signal 38. Forexample, the acoustic return signal 38 may have a frequency ofapproximately 30 to 80, 35 to 75, 40 to 60, or 45 to 55 Hertz. Asmentioned above, the transceiver 84 of the AFID 15 may send the acousticreturn signal 38 using an Ethernet protocol. In this manner, thetransceiver 84 may communicate with the MAT 14 only when no other AFID15 is communicating with the MAT 14. For example, the transceiver 84 ofthe AFID 15 may monitor and detect acoustic communications by the MAT 14or other AFIDs 15. More specifically, if no acoustic communications aredetected from the MAT 14 or other AFIDs 15, the AFID 15 may wait arandom length of time (e.g., 10 to 20 milliseconds), and if acousticcommunications from the MAT 14 or other AFIDs 15 are still not detected,the AFID 15 may broadcast the acoustic return signal 38 containing thesensor measurement data. As a result, the acoustic frequencyinterrogation and data system 12 may have multiple AFIDs 15communicating with one MAT 14.

After the sensor measurement data is transmitted to the MAT 14, the AFID15 will shut down once the power generated from the high-power acousticactivation signal 36 runs out. In other words, the sensor 88 will shutdown and stop taking sensor measurements when the power generated fromthe high-power acoustic activation signal 36 runs out. Upon the receiptof another high-power acoustic activation signal 36 from the MAT 14, theAFID 15 will generate additional power and resume taking andtransmitting sensor measurements to the MAT 14, in the manner describedabove.

FIG. 5 is a schematic of the electronics circuitry 52 of the MAT 14. Inthe illustrated embodiment, the electronics circuitry 52 includes apower supply 120, a system interface module 122, and a communicationsmodule 124. As discussed above, the electronics circuitry 52 is coupledto the subsea instrumentation system 34. More specifically, the subseainstrumentation system 34 is coupled to the power supply 120 and thesystem interface module 122 of the electronics circuitry 52. The powersupply 120 is configured to provide the power required to broadcast thehigh-power acoustic activation signal 36. For example, the power supply120 may be an AC power supply, or a DC power supply, such as a battery.

As shown, the power supply 120 supplies power to the system interfacemodule 122 and the communications module 124. As mentioned above, thesystem interface module 122 is coupled to the subsea instrumentationsystem 34. Additionally, the system interface module 122 communicateswith the subsea instrumentation system 34. For example, the systeminterface module 122 may receive commands or other instructions from thesubsea instrumentation system 34. In certain embodiments, the subseainstrumentation system 34 may provide instructions regarding the timing,length, or magnitude of the high-power acoustic activation signal 36 tobe generated by the MAT 14. Thereafter, the system interface module 122may communicate the instructions to the communications module 124, whichis coupled to the transceiver 54 of the MAT 14. For example, thecommunications module 124 may direct power from the power supply 120 tothe transceiver 54 based on instructions received from the systeminterface module 122. Based on the instructions received from the systeminterface module 122, the communications module 124 may direct thetransceiver 54 to generate a particular high-power acoustic activationsignal 36.

Additionally, as discussed above, the transceiver 54 is configured toreceive the acoustic return signal 38 containing sensor measurement datafrom the AFID 15. Upon receiving the acoustic return signal 38, thetransceiver 54 communicates the acoustic return signal 38 to thecommunications module 124, which then communicates the acoustic returnsignal 38 to the system interface module 122. Subsequently, the systeminterface module 122 may communicate the acoustic return signal 38containing the sensor measurement data to the subsea instrumentationsystem 34 for storage, analysis, further communication, etc.

FIG. 6 is a schematic of the electronics circuitry 86 of the AFID 15. Asshown, the electronics circuitry 86 of the AFID 15 includes acommunications module 140, an AC/DC micropower supply 142, a capacitor144 (e.g., an ultracapacitor), and a sensor processing module 146. Thetransceiver 84 is coupled to the communications module 140 and the AC/DCmicropower supply 142. As discussed above, the electronics circuitry 84is configured to generate power from the high-power acoustic activationsignal 36 broadcasted by the MAT 14. Specifically, the high-poweracoustic activation signal 36 received by the transceiver 84 of the AFID15 is communicated to the AC/DC micropower supply 142. The AC/DCmicropower supply 142 generates an alternating voltage from thehigh-power acoustic activation signal 36, and the alternating voltage isthen rectified and stored in the capacitor 144. The stored electricalpower in the capacitor 144 is subsequently used to power thecommunications module 140 and the sensor processing module 144.

Using power from the capacitor 144, the sensor processing module 146executes data acquisition instructions and activates the sensor 88. Oncethe sensor 88 takes one or more measurements, the sensor processingmodule 146 transmits the sensor measurement data to the communicationsmodule 140. Thereafter, the communications module 140 communicates thesensor measurement data to the transceiver 84, which broadcasts thesensor measurement data as a part of the acoustic return signal 38. Inthe manner described above, the acoustic return signal 38 is thenreceived and processed by the MAT 14.

While the invention may be susceptible to various modifications andalternative forms, specific embodiments have been shown by way ofexample in the drawings and have been described in detail herein.However, it should be understood that the invention is not intended tobe limited to the particular forms disclosed. Rather, the invention isto cover all modifications, equivalents, and alternatives falling withinthe spirit and scope of the invention as defined by the followingappended claims.

1.-20. (canceled)
 21. An acoustic frequency interrogation and datasystem, comprising: a master acoustic transceiver configured tobroadcast an acoustic activation signal, wherein the acoustic activationsignal comprises a high-power tone and an acoustic message, and whereinthe high-power tone comprises at least 10 watts; and an acousticfrequency interrogated data transmitter comprising a sensor, wherein theacoustic frequency interrogated data transmitter is configured togenerate power from the high-power tone of the acoustic activationsignal and activate the sensor to measure an operating parameter of aworking system using the acoustic message portion of the acousticactivation signal.
 22. The system of claim 21, wherein the sensor of theacoustic frequency interrogated data transmitter is configured to shutdown when the power generated from the high-power tone of the acousticactivation signal is consumed by the acoustic frequency interrogateddata transmitter.
 23. The system of claim 21, wherein the masteracoustic transceiver comprises electronic circuitry comprising a powersupply, a system interface module, and a communications module.
 24. Thesystem of claim 23, wherein the power supply is configured to providepower to the system interface module and the communications module, thesystem interface module is configured to communicate with aninstrumentation system of the working system, and the communicationsmodule is configured to broadcast the acoustic activation signal andreceive an acoustic return signal from the acoustic frequencyinterrogated data transmitter.
 25. The system of claim 21, wherein theacoustic frequency interrogated data transmitter comprises electroniccircuitry comprising a communications module, an alternating current(AC)/direct current (DC) micropower supply, and a sensor processingmodule.
 26. The system of claim 25, wherein the communications module isconfigured to receive the acoustic message of the acoustic activationsignal, receive feedback from the sensor indicative of the operatingparameter of the working system, and send an acoustic return signal tothe master acoustic transceiver.
 27. The system of claim 25, wherein theAC/DC micropower supply is configured to receive the high-power tonefrom the acoustic activation signal, generate an alternating voltage,and supply power to the communications module and the sensor processingmodule.
 28. The system of claim 25, wherein the sensor processing moduleis configured to execute instructions to activate the sensor to measurethe operating parameter of the working system and to send feedbackindicative of the operating parameter of the working system to thecommunications module.
 29. The system of claim 21, wherein the acousticfrequency data transmitter is configured to be partially mounted withinan opening of subsea equipment.
 30. The system of claim 21, wherein themaster acoustic transceiver is connected to a subsea instrumentationhousing.
 31. The system of claim 21, comprising a plurality of theacoustic frequency data transmitters, wherein each acoustic frequencydata transmitter of the plurality of acoustic frequency datatransmitters is configured to communicate with the master acoustictransceiver.
 32. The system of claim 31, wherein the master acoustictransceiver is configured to broadcast the acoustic activation signal toeach acoustic frequency data transmitters of the plurality of acousticfrequency data transmitters.
 33. The system of claim 31, wherein eachacoustic frequency data transmitter of the plurality of acousticfrequency data transmitters communicates data to the master acoustictransceiver in series with one another.
 34. The system of claim 33,wherein each acoustic frequency data transmitter of the plurality ofacoustic frequency data transmitters communicates data to the masteracoustic transceiver at a different frequency.
 35. A method, comprising:outputting an acoustic activation signal from a master acoustictransceiver; receiving the acoustic activation signal at an acousticfrequency data transmitter; converting the acoustic activation signalinto electrical power; directing the electrical power to a sensor of theacoustic frequency data transmitter to power the sensor; measuring anoperating parameter of a working system with the sensor; sendingfeedback indicative of the operating parameter from the acousticfrequency data transmitter to the master acoustic transceiver; andreceiving the feedback at the master acoustic transceiver.
 36. Themethod of claim 35, comprising sending the feedback from the masteracoustic transceiver to an instrumentation system and adjusting acomponent of the working system with the instrumentation system based onthe feedback.
 37. The method of claim 35, wherein converting theacoustic activation signal into electrical power comprises using analternating current (AC) and direct current (DC) micropower supply ofthe acoustic frequency data transmitter to generate the electrical powerfrom the acoustic activation signal.
 38. The method of claim 37,comprising storing the electrical power in a capacitor of the acousticfrequency data transmitter before directing the electrical power to thesensor.
 39. The method of claim 35, comprising shutting down the sensorwhen the electrical power generated from the acoustic activation signalis consumed by the acoustic frequency data transmitter.
 40. An energyharvesting system for a subsea system, comprising: a subsea structure ofthe subsea system comprising a frame and a support structure; a masteracoustic transceiver coupled to the support structure of the subseastructure, wherein the master acoustic transceiver is configured tobroadcast an acoustic activation signal using a first transceiver; andan acoustic frequency interrogated data transmitter coupled to the frameof the subsea structure, wherein the acoustic frequency interrogateddata transmitter comprises a sensor, a second transceiver, andelectronic circuitry, and wherein the acoustic frequency interrogateddata transmitter is configured to receive the acoustic activation signalat the second transceiver, generate power from the acoustic activationsignal using the electronic circuitry, and activate the sensor tomeasure an operating parameter of a working system using the acousticactivation signal.